


Elegant Solution For Three

by Varewulf



Category: BanG Dream! (Anime), BanG Dream! Girl's Band Party! (Video Game)
Genre: F/F, Fluff and Angst, Multi, Polyamory, Yuri
Language: English
Status: Completed
Published: 2018-11-15
Updated: 2018-11-15
Packaged: 2019-08-24 03:22:26
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,803
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16631939
Author URL: https://archiveofourown.org/users/Varewulf/pseuds/Varewulf
Summary: Wrote some polyam for Kasumi, Arisa, and Saaya, in four parts.Part 1: Arisa and SaayaPart 2: Kasumi and SaayaPart 3: Arisa and KasumiPart 4: All three togetherProbably could have made it four chapters, but it felt like too much work.





	Elegant Solution For Three

**Author's Note:**

> My first Bandori polyam. Okay, so, see, here's the thing. Since it was pointed out to me, I have paid more attention, and seen some of what people say about Arisa and Saaya. And the anime had some clear hints of Kasumi and Saaya. But! KasuAri is like... the third most important couple in all of anime for me, so breaking them up in any context is simply out of the question. So I thought... maybe I can put them into a polyamorous relationship with Saaya instead, to have some room to explore those dynamics without betraying my soul.
> 
> From the start the intention was to check in on them after they'd been together for a little while, and had settled in a bit. I had not initially meant to make it so much of a retrospective reflection though. But that's what I ended up writing, so there we go. I wanted to try out the different combinations, before having all three together at the end. I'd like to do more with this trio in the future at some point, now that I have done the establishing set-up for them.

_Message from: Kasumi_

" _I got it! I'll date you both!_ "

"Eh?" uttered Saaya sitting in her room.

"What?" said Arisa out in her garden.

* * *

_Some time later_

Saaya had been to the bathroom, and on her way back she spotted someone hunkered down in a secluded spot. There weren't many people in school with blonde hair like that. It wasn't like she had to go back right away, so...

"Hey, Arisa~," she said as she walked closer.

Arisa jumped as if startled, and stared at Saaya with wide eyes for a second, then visibly relaxed. "Oh, it's just you," she said.

"Just me? Ouch," Saaya said.

"You know what I mean," Arisa said. "I was worried it was someone I didn't know." She had some paperwork with her.

"What's that?" Saaya asked.

"Huh? Oh, just some stuff for class," Arisa said with a shrug. "Need to work out a schedule for an upcoming project. Came here to work alone."

"Do you want me to leave you alone, then?" Saaya asked.

"Uh..." Arisa looked up at her. "No, it's fine. You can stay if you want." She tried to look around Saaya. "Where's Kasumi?" she asked.

"Attending to her class duties," Saaya said.

"Huh... I still can't believe your class chose her to be the rep," Arisa said.

"Hey now, that's a bit harsh. She likes helping people," Saaya sat down by Arisa. "Just like you."

Arisa blushed a little. "I guess..." she mumbled.

"I figured as a fellow class rep, you'd understand," Saaya said with a smile.

"Eh? I'm not class rep," Arisa said.

"Oh?"

"I wasn't even there when they were picked."

"Well, your class acts as if you are. They're always saying how reliable you are." Saaya grinned at Arisa.

"Mmph..." Arisa harrumphed, and looked back at her papers. "If you're just going to be a nuisance, then you might as well leave. I need to concentrate."

Saaya suppressed a giggle. "I'll be quiet," she said. Arisa could be really cute.

"Good," Arisa said. She seemed to be on guard for a little bit longer, but when Saaya indeed kept quiet as promised, she relaxed again, and focused on what she was doing.

Saaya smiled. _She's such a hard worker_ , she thought. While Kasumi wasn't exactly a slouch either, it was hard to imagine her getting through paperwork as quickly as Arisa was doing.

Back when this had all started, Arisa and Saaya had seen each other more as rivals than girlfriends. Neither of them had wanted to back down, to deal with the potential regret, so they had agreed to this three-person relationship. But both of them had expected that it was only a matter of time before Kasumi made her final, real choice between them. They hadn't been familiar with the concept of there being more than two people in a romantic relationship, but they had since learned that it wasn't as unheard of as they thought. Whether Kasumi had known that before suggesting it was a different matter.

Yet as time passed, and Kasumi showered them both with affection, not showing any signs of wanting to cast either aside, they had started to appreciate each other's company more too. They just had to start relaxing around each other. It had taken a bit of time, and maybe they still weren't as close to each other as either of them were to Kasumi, but they no longer felt any urge to compete. They were in this together, and honestly that wasn't so bad.

Arisa was actually really cute, caring, and sweet; she was just very defensive. Reluctant to let people get close. Saaya wondered if anything had happened to cause that, but she wasn't sure if it was right to pry into it. At least not yet. Maybe Arisa would open up to them eventually. For now it was nice that Arisa had become comfortable with Saaya's presence. That was a big leap from where they had started. Not that they had ever disliked each other, but... things had definitely been awkward. For a time Saaya had worried what the fallout would be if Kasumi had decided to pick one over the other. Now she was hopeful it would never come to that.

Arisa put her pen down. "Okay, done," she said quietly, probably to herself, though Saaya could still hear it. Then she started sorting her papers together.

Saaya got an idea. A wicked idea. "Hey, Arisa. Look here for a moment," she said.

"Hm?" Arisa turned her head, and Saaya immediately seized the chance to plant a quick smooch on her lips. The look of surprise on Arisa's face was exactly what she had hoped for.

Saaya couldn't help laughing.

Arisa was blushing. "Eesh... both you and Kasumi love your little ambushes..." she said in a grumpy tone.

"Ahaha, sorry," Saaya said. "It's just that you're so cute when-" And that was as far as Saaya got before Arisa grabbed her by the collar, and pulled her into a kiss. No quick smooch this time. Saaya even felt Arisa's tongue probe against her lips, but she was too shocked to react.

Arisa let Saaya go. "If you're going to kiss me, at least do it properly," she said, collected her papers, and got up.

"Uh... oh... okay," Saaya said. She was too dazed to move.

"See you later~," Arisa said sweetly before she walked off.

"Yeah, sure... yeah..." Saaya watched her go, not able to think of anything else to say.

She gradually came to her senses once Arisa was out of sight. And managed to get to her feet. That had been just about the last thing she had expected. Maybe it was dangerous to underestimate Arisa. Though it had certainly been thrilling.

* * *

It was a relatively quiet time at the convenience store. Saaya preferred to go shopping at those times. She knew everyone, and everyone knew her, so it could take a while if everyone wanted to chat. That was fair enough when she wasn't in a hurry, but for grocery shopping she preferred to get home quickly, especially if she was buying any fresh goods.

"Saaaaaaaaaya!"

That was all the warning Saaya got before someone hugged her from behind.

"Uwah! Kasumi?!" She got startled by the sudden embrace, but thankfully managed to not drop anything.

"Ehehe, gotcha!" Kasumi said, sounding very pleased with herself.

"I didn't expect to find you here," Saaya said. Even if maybe it was more the other way around.

"I picked up your scent outside, and followed the trail inside," Kasumi said cheerfully. It didn't sound like she was joking.

"You followed my scent? That's... incredible, honestly," Saaya had to admit. "And maybe a little worrying..."

"Huh? Why? Is it creepy?" Kasumi asked.

Saaya giggled. "Maybe, but... I don't mind if you smell me," she said, and gently stroked Kasumi's hand.

The very first time they had met, at the first day of high school, Kasumi had also 'spotted' Saaya by her smell. Saying something like " _you smell like fresh bread_ ". She didn't remember the exact wording any longer. Saaya still wasn't entirely sure if it was truly that obvious, but everyone else was too polite to say anything, or if Kasumi's nose was exceptionally good. It might be the latter, if she had truly followed Saaya's scent trail.

Kasumi seemed happy. "So what are you doing?" she asked.

"Shopping," Saaya said in an 'isn't it obvious' tone. "We ran out of a few things at the bakery, and I was asked to get something for dinner while I was out." Kasumi let go of her, so she could get back to it.

Saaya's parents were good at keeping the bakery stocked, but it was virtually impossible to keep track of everything all the time, and unforeseen things could occur whenever. So doing the occasional extra shopping trip was part of the business. Plus it was a chance to spoil her little siblings more. She was getting a small box of chocolate milk for Jun, and strawberry milk for Sana. The kind that came with a straw.

"I'll help!" Kasumi said without hesitation. "I can carry half! Or am I supposed to carry all...?" The final part seemed more like a question to herself.

It honestly wasn't that much. Saaya doubted she'd have any trouble carrying it alone. But she didn't want to point that out when Kasumi was being sweet. "I appreciate it," she said instead. The way Kasumi beamed was beautiful.

It had probably begun with Saaya admiring Kasumi's courage and determination. It was hard to say for sure. It wasn't like a switch had been flipped, and suddenly she was in love, when she hadn't been the night before.

Honestly Kasumi had seemed like a bit much in the beginning, but her strong presence could be comforting. Saaya had started appreciating it. When the whole mess with Saaya agonising over whether to or not to join the band was going on, Kasumi never gave up, but she was also supportive rather than being too pushy. Sure, she had been a little pushy, but Saaya probably needed that. Needed a push to realise what she actually wanted. And that it wasn't impossible to both follow her dreams, and look after those she cared for. That it was okay to want something for herself.

Somewhere along the way a crush on Kasumi had developed, and with her newfound confidence, Saaya had decided to confess. But so did Arisa. Kasumi had said she'd think about it. Which had turned into their current situation.

Saaya had considered stepping down. To give up. From the first time she had seen Arisa and Kasumi together, before she had realised any feelings of her own, she had seen how attached Arisa had become to Kasumi. Kasumi had probably been a lifeline out of misery for both Saaya nor Arisa, that neither had even been aware they were stuck in. So Saaya had been prepared to sacrifice her own happiness once again. Felt that maybe she had overstepped. Wanted too much. But now she was glad she hadn't. Maybe Kasumi wouldn't have let her, but it was probably better that she hadn't needed to find out.

The headed out of the store carrying one bag each. Saaya had ended up buying a little more than planned.

"Thanks for the help," she said.

"No problem! I gotta be a good girlfriend, after all," Kasumi said proudly. She really wasn't the type to take anything easy. Well, not anything she cared about, at least. The same might not always hold true for anything else.

"Haha, good point," Saaya giggled, and moved her bag to her other hand, so she could link arms with Kasumi. "When we get home, maybe I can find some way to reward you in my room?" She tried her best to be smooth, but it was hard to say something like that without blushing at least a little.

"Oh?" Kasumi sounded intrigued. She entwined her fingers with Saaya's, and gave her hand a soft squeeze. "I'll be looking forward to it, dear~."

"Dear? I'm not your wife yet," Saaya said without fully thinking about her phrasing.

Kasumi's eyes twinkled. "Ooohhhhh~? Yet~?" She grinned wide.

Saaya blushed deeply. "I-I mean... ugh..." She wasn't sure what to say in the face of Kasumi's smug expression.

Hopefully they'd get inside soon.

* * *

Arisa went to answer the door. She wasn't expecting anyone, and wasn't sure what sort of person would show up unannounced on a Sunday. Door to door salesman? If that was the case, then she definitely didn't want anything of anything. She was tempted to not answer at all, but it wasn't fair to leave it to her grandmother. She was probably resting this time of day.

She took a breath before opening the door. "Ye- Kasumi?"

"Arisa..." Kasumi voice was weak, and cracked. Barely a croak. It was obvious she had been crying.

"H-hey, what's wrong?" Arisa asked.

"Nothing..." Kasumi said, and stumbled through the door, burying her face in Arisa's shoulder.

"Whoa!" Arisa managed to brace for it in time, and not fall over. "What happened?" she asked.

"N-nothing, it's just... it's nothing," Kasumi said, and seemed like she was about to start crying again.

"Ah." Arisa put an arm around Kasumi, and closed the door. "Come on in. I guess you can stay until the nothing goes away," she said calmly.

"Okay." Kasumi let Arisa lead her to her room.

It didn't seem like Kasumi was hurt physically, so Arisa wasn't sure what might have happened. The thing with Kasumi was that she tended to feel things very strongly. So most of the time she was very bubbly, and all over the place. When she was affectionate it was almost impossible to get her off of you. Which wasn't necessarily a bad thing. But when she got sad, it was as if she was totally heart-broken. It might be something serious, or something that didn't seem like such a big deal. So unless she told you, it was hard to judge the severity of what had caused it.

The important thing was to take care of her. Arisa had leaned on Kasumi more than once. She didn't mind returning the favour if needed, even if she wasn't sure whether she was as good at it.

Arisa eased Kasumi down to sit on her bed. Somewhere soft was probably preferable right now.

"Do you want me to get you something?" she asked.

Kasumi gently shook her head.

"I'm sure you'll feel better if I get you some tea," Arisa said, but as soon as she started to turn away, she felt something tug on her skirt. She looked down to see Kasumi holding on to it. "I'll be right back," she said, but Kasumi didn't let go. She sighed a little. "Want me to sit with you?"

Kasumi nodded.

Arisa still thought tea would probably help things, but she could understand the feeling of not wanting to be alone. "Alright," she said, and sat down next to Kasumi. Who immediately leaned against her.

"Sure you don't want to talk about it?" Arisa asked, and started stroking Kasumi's hair. It was a little amazing how solid those cat ear shapes felt. She had always wondered how Kasumi made them that way.

Kasumi nodded again.

"Okay, okay," Arisa said, giving up for now. She leaned her head against Kasumi's.

It had been a weird year. Before Kasumi arrived, Arisa's existence had been a strange one. Her parents were gone. She'd had no friends. At school she had been regarded as a cryptid, considering how little she was present. But she had felt at ease with her grandmother, and her bonsai.

Then suddenly this whirlwind of a girl had stumbled into her life, and thrown everything into chaos. At the time she had thought she hated it, but looking back on it now she could see how quickly she had latched on for dear life. She would hold on to Kasumi's clothes for safety, like Kasumi had just done to her. Something about her had cracked Arisa's walls right away. She had still fought to keep Kasumi at a distance, but it had been impossible to keep up her proper lady act around her. That had shattered immediately.

She didn't like letting anyone get close. It was too risky. It had never ended well. Her grandmother was the only one she trusted. Or the only one she _had_ trusted, at least. By the time it had dawned on her how important Kasumi had become, it had been too late to do anything to stop it. She just hadn't wanted to admit it openly. She had thought that just staying close was enough. That having the band was enough.

Until she had heard from Rimi that Saaya had confessed to Kasumi. She probably should have seen that coming, but somehow it had been a complete blind spot to her before hearing that. Too wrapped up in her own feelings, perhaps. So she had panicked. And hurriedly dragged Kasumi aside to make her own messy confession. It had been the least dignified moment of her life, but all she had been able to think about was that she didn't want her feelings to be left unsaid.

The wait for a reply had been grueling. For both of them, probably. Arisa didn't feel like she had a lot to offer compared to Saaya. If Kasumi wanted a good girlfriend, Saaya was obviously the better option. Arisa had a hard time being open and honest. She was smart, but she wasn't good at practical things. She wasn't social, and didn't know anyone. She could neither cook, nor bake, very well. She was sure she could be accurately described as 'high-maintenance'. But even knowing all of that, she hadn't been able to be quiet. She'd had to try to sabotage things for Saaya. So she couldn't really call herself a good friend either.

Then Kasumi had come up with her own third option solution, which somehow seemed to be working out. Arisa was growing closer to Saaya too, little by little. While she wasn't about to admit it to anyone, Arisa had read about polyamory online, like she had read about a lot of other things. It just hadn't occurred to her as something she'd ever end up in. Nor that Kasumi would know of it. Or maybe Kasumi had come up with it on her own, it was hard to say for sure with that girl.

She suddenly realised that Kasumi was asleep. Tired herself out, most likely. So she eased her down onto the bed, and into a more comfortable position. Maybe once she woke up she'd be willing to talk. At the very least she should feel better. It was probably a good idea to text Asuka to let her know where her sister was, just in case Kasumi was supposed to do something with her family today.

Kasumi looked very peaceful. Arisa brushed the hair out of Kasumi's face, and gently kissed her forehead. Then an idea occurred to Arisa. A very wicked idea.

She had seen pictures of Kasumi and Asuka when they were younger, and Kasumi's hairstyle used to be different. A pair of cute pigtails. So Arisa wondered what Kasumi would look like with that hairstyle today. She had spare hairbands, and a helpless Kasumi at her disposal. Maybe it was wrong to take advantage of someone like that, but the temptation was great.

A short time later the deed was done. Now all that was left was to take a picture, and send it to Saaya.

* * *

Arisa and Saaya were sitting next to each other on the couch, with Kasumi stretched out on her stomach across their laps.

"You know... sometimes I wonder if you just wanted to date us both so you could have a double lap pillow," Arisa said snarkily.

"Of course not! It's just a nice benefit," Kasumi said cheerfully.

"Just like a cat," Saaya said, and scritched Kasumi's neck.

"H-hey, that tickles!" Kasumi squirmed.

"Oh really?" Saaya and Arisa exchanged looks, then as if they were thinking exactly the same thing, they started tickling Kasumi at the same time.

"Aaaahhhahahaha, noooo, meeerrrrrcyyyyy, aaahhhh!" Kasumi was trapped, and helpless. Thankfully the assault didn't last long. She took deep breaths to recover her composure. "That was mean," she said accusingly.

"Sorry, you were just such a tempting, open target," Saaya said playfully.

Arisa just giggled.

Kasumi decided to get up rather than risk another attack. Though in a sense she was happy to see how in sync Arisa and Saaya had become. She had been quite nervous when she first suggested this relationship. She had tried her best to pretend she wasn't, but she had no idea whether it had still been obvious.

She was willing to admit that she could be quite dense. Maybe not out loud, but at least to herself. When Saaya had confessed to her, she hadn't seen it coming at all. So she had asked for time to think it over. Maybe that had been insensitive, but she had been too surprised to give an answer on the spot. And maybe in hindsight that had been a good thing.

Somehow Arisa had found out, and also confessed to Kasumi the next day. Which hadn't made things any easier. How could she have missed two people having feelings for her? Then she had agonised over what to do, what to decide. She had wanted to think it over, but also hadn't wanted to leave them waiting for too long. Trying to pick one over the other had been horrible. She loved them both, even if she hadn't considered whether it could work as romantic love before then.

So she had picked the third option. Say yes to both. She was fairly certain she had heard of such things before, even if she couldn't say where. Letting one of them down was too hard. So it was either that, or saying no to both. She had also worried whether saying no to one or both would break up the band. Maybe that was a selfish consideration, but it had been on her mind. When they had agreed, she had felt relieved, and happy.

But making it work had been scary. She might be dense, but she hadn't been ignorant of how the two of them had kept some distance between each other at the start. She hadn't been sure what else to do but love them both as best she could, so that's what she had gone for. Eventually the two of them seemed to get closer. Hopefully that meant this was all working out. At this point she couldn't imagine being without either of them.

Thinking of all of this was making her rather emotional. She got down, and hugged them both close.

"H-hey!"

"Whoa!"

"I love you," Kasumi said to them in a soft voice.

"Kasumi?" Saaya sounded a little surprised, but instead of asking anything further, she relaxed, and put her arms around Kasumi and Arisa to join the hug. "I love you too," she said warmly.

A moment later Arisa also joined in. "Yeah, me too," she said.

"Mmph. Arisa, you gotta say it properly," Kasumi demanded, and hugged tighter. Maybe sounding a little grumpy.

"W-what?" Arisa sounded a little flustered.

Saaya giggled. "Come on," she said encouragingly.

Arisa blushed. "Mm... alright, fine." She smiled. "I love you too."

Kasumi cheered up immediately. She pulled her head back to plant a kiss on Arisa's pink cheek. Saaya leaned over, and did the same to the other cheek. Which only seemed to deepen Arisa's blush.

They could make this work. Kasumi was sure of it.

**Author's Note:**

> The four parts I had roughly figured out from the start, but with my creative energy being quite low lately, it took me longer to write them down than it usually does. I think I'm okay with how they turned out, though.
> 
> Arisa and Saaya having gotten closer, but maybe not quite reached lovey-dovey status yet was an obvious candidate for part one. Seeing someone say that a polyam relationship is still valid even if not everyone in it is equally close to everyone else was part of my inspiration behind this.
> 
> As for whether Kasumi is truly 1-A's class rep, I am not entirely certain. I seem to remember her being chosen from the anime, but looking back I think that was for something else. Maybe. Still! It's an interesting enough idea that I went for it anyway. I feel like the anime portrayed Kasumi as a better student than the game hints at her being. Waking up early, friendly with everyone, eager to help out. Also not entirely sure if it's class representative, or class president. Maybe it can be translated either way.
> 
> For part two I just wanted some KasuSaaya goofing around. Kasumi smelling Saaya has amused me since the start, so I wanted to incorporate that.
> 
> In part three... I feel like I've written a fair amount of stories with Arisa leaning on Kasumi for support, so I wanted to do something that was more of the opposite for this one. Though to be honest, the reason I don't specify what happened to Kasumi is because I couldn't think of anything that wasn't either too serious, or too trivial to trigger such a response from her. So I decided to just leave it vague and open. I knew the scenario I wanted, but couldn't think of a good reasoning for getting there, so I just did it anyway.
> 
> And finally in part four I wanted more fluffy goofing again.


End file.
